(1) Field of the Invention
The present invention relates to an improved trap fitting assembly which prevents smoke and fire from spreading through the fitting which is preferably mounted through a tub box mounted in a flammable floor. In particular, the present invention relates to a trap fitting assembly including a flammable T-connector mounted inside of a non-flammable threaded nipple which extends part of the way through an opening in the bottom of a tub box or other non-flammable support means that is mounted in the floor. A non-flammable J-pipe is connected to an extension portion of the threaded nipple below the tub box. Water is trapped in the J-pipe so that any smoke or fire burning in a building will not be able to travel through the J-pipe, the threaded nipple or the tub box.
(2) Prior Art
Trap fitting assemblies are well known and generally include a non-flammable main conduit which penetrates a floor along a vertical longitudinal axis and a non-flammable J-pipe which is connected to a lower most end of the main conduit Generally, the J-pipe is provided through a pre-formed opening in the floor which is larger in diameter than the conduit. The J-pipe is preferably held in place by drain or tub box structure mounted on or in the floor. This construction is expensive.
My U.S. Pat. No. 4,724,858 describes a firestop stack fitting for sealing the opening of pipes which extend between floors of a building. A non-flammable sleeve is mounted inside a flammable coupling. This fitting works well where a trap is not required.
My U.S. Pat. No. 4,953,235 describes a trap fitting assembly, preferably adapted for a floor drain outlet or tub box, which prevents the spread of fire and smoke through a concrete floor of a building. The fitting uses a flammable coupling embedded in a poured concrete floor. A non-flammable sleeve inside the coupling has an extension portion extending below the floor. A non-flammable J-pipe contains water at a level above the trough of the two upturned legs of the J-pipe. The J-pipe is connected to the extension portion and prevents smoke and fire from going through the floor. This trap fitting assembly is not adapted for use with flammable floors.